Thin Film Transistor, TFT is current leakage when applied to the gray scale voltage, resulting flicker phenomenon in Liquid Crystal Display, LCD display, and affect the performance of the display. In order to prevent the gray scale changes of the pixel electrode caused by leakage and improve or avoid flicker, the LCD need to have a larger storage capacitor. But a larger storage capacitor is required two electrodes with larger size, ie, the common electrode and the pixel electrode in the array substrate with larger size, which will undoubtedly reduce the aperture ratio of the pixel.